The present invention relates to a control method of an embossing apparatus for performing embossing by pressing a processing tool against a sheet-like medium to be processed.
An embossing apparatus for performing embossing on a sheet-like medium to be processed is disclosed in, e.g., Japanese Patent Laid-Open No. 2001-277353 (literature). This embossing apparatus disclosed in the literature includes a platen roller having a function of feeding a belt-like medium to be processed, and an embossing tool to be pressed against the medium to be processed on this platen roller. The belt-like medium to be processed is used as it is pulled out from a supply reel arranged adjacent to the platen roller.
The platen roller is formed into a cylindrical shape having a size by which the medium to be processed can be wound, and rotates when driven by a driving device. The outer circumferential surface of this platen roller is elastic. Also, sprockets are formed in the two end portions of the platen roller in the axial direction. These sprockets engage with large numbers of feed holes formed on the two side portions of the medium to be processed, and feed the medium to be processed in the longitudinal direction as the platen roller rotates.
The embossing tool has a rotatable ball to be pressed against the medium to be processed. This embossing tool is supported by a tool head, and arranged in a position above the platen roller and opposite to the platen roller with the medium to be processed being sandwiched between them. The tool head has a function of selectively pressing the embossing tool against the medium to be processed, and a function of moving the platen roller together with the embossing tool in the axial direction.
In this embossing apparatus, an embossed portion having a recess is formed on the medium to be processed by pressing the ball of the embossing tool is pressed against the medium to be processed. Embossing is performed by operating the platen roller and tool in a state in which the embossed portion is thus formed. The embossed portion extends in the longitudinal direction of the medium to be processed when the platen roller rotates. The embossed portion also extends in the widthwise direction of the medium to be processed when the tool head moves in the axial direction of the platen roller. That is, the embossing apparatus disclosed in the literature can perform embossing on an arbitrary shape because the platen roller and tool head cooperate with each other.
Unfortunately, the embossing apparatus disclosed in the literature has the problem that it is difficult to perform embossing by which the shape of an embossed portion is clear. This is so probably because the boundary between a non-embossed portion and embossed portion is not bent but pulled.